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Resumption of post-partum oestrous behaviour and associated plasma progesterone profiles in Menz ewes

Published online by Cambridge University Press:  02 September 2010

E. Mukasa-Mugerwa
Affiliation:
Animal Reproduction and Health Section, International Livestock Centre for Africa, PO Box 5689, Addis Ababa, Ethiopia
Zere Ezaz
Affiliation:
Animal Reproduction and Health Section, International Livestock Centre for Africa, PO Box 5689, Addis Ababa, Ethiopia
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Abstract

Fifty Ethiopian Menz ewes maintained on pasture grazing with uncontrolled mating showed ovarian cyclicity at all times of the year. Conception rates to first, second and third service were 78, 18 and 4%, respectively. Mean post-partum anoestrous interval was 76·1 (s.e. 4·6) days. Two-thirds of ewes conceived before lamb weaning at 90 days and had 8 month lambing intervals. Twice weekly progesterone determinations showed that 67% of ewes exhibited a silent ovulation 66·4 (s.e. 10·5) days post partum, 12% of oestrous cycles were longer than 20 days and 8% of heats were false or anovulatory. It was concluded that Menz ewes have the natural potential for three lambings in 2 years, under adequate nutrition. Their better management and genetic improvement should further reduce current lambing intervals and increase annual reproductive rates.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1991

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References

REFERENCES

Amir, D., Rosenberg, M. and Schindler, H. 1984. Oestrpus and ovarian activities of Finn-cross ewes during the post-partum and the seasonal anoestrous periods. Journal of Agricultural Science, Cambridge 103: 155160.CrossRefGoogle Scholar
Evans, G. and Robinson, T. J. 1980. Reproductive potential and endocrinological responses of sheep kept under controlled lighting. 1. Comparative reproductive performance of four breed types of ewe. Animal Reproduction Science 3: 2337.CrossRefGoogle Scholar
Feldman, S. D., Valencia, M. J. and Zarco, Q. L. 1988. Postpartum ovarian activity of the ewe in Mexico. 11th International Congress on Animal Reproduction and Al, Dublin, Ireland, Vol 2, pp. 29.Google Scholar
Gonzalez, A., Murphy, B. D., Alba, J. M. de and Manns, J. G. 1987. Endocrinology of the postpartum period in the Pelibuey ewe. Journal of Animal Science 64: 17171724.CrossRefGoogle ScholarPubMed
Lamming, G. E., Wathes, D. C. and Peters, A. R. 1981. Endocrine patterns of the postpartum cow. Journal of Reproduction and Fertility, Suppl. 30, pp. 155170.Google Scholar
Land, R. B. 1971. The incidence of oestrus during lactation in Finnish Landrace, Dorset Horn and Finn- Dorset sheep. Journal of Reproduction and Fertility 24: 345352.CrossRefGoogle ScholarPubMed
Mattoni, M., Mukasa-Mugerwa, E., Cecchini, G. and Sovani, S. 1989. The reproductive performance of East African (Bos indicus) zebu cattle in Ethiopia. I. Estrous cycle length, duration, behavior and ovulation time. Theriogenology 30: 961971.CrossRefGoogle Scholar
Mukasa-Mugerwa, E., Tegegne, A., Mattoni, M. and Cecchini, G. 1989. Effect of oestrous synchronization with prostaglandin F2a in Ethiopian highland Zebu (Bos indicus) cows. Animal Production 48: 367373.Google Scholar
Novoa, C. 1984. The post-partum ewe. Proceedings of 10th International Congress on Animal Reproduction and Al, Urbana, USA, Vol VII, pp. 2430.Google Scholar
Osinowo, O. A. and Ekpe, G. A. 1985. Postpartum intervals to oestrus and conception in Yankasa sheep. Journal of Agricultural Science, Cambridge 104: 253255.CrossRefGoogle Scholar
Rhind, S. M., Robinson, T. J., Chesworth, J. M. and Phillippo, M. 1980. Effects of season, lactation and plane of nutrition on the reproductive performance and associated plasma LH and progesterone profiles in hormonally treated ewes. Journal of Reproduction and Fertility. 58: 127137.CrossRefGoogle ScholarPubMed
Rodriguez Iglesias, R. M., Giglioli, C, Latimori, N. and Irazoqui, H. 1987. Ovulation rate of Lincoln ewes at Bahia Blanca, Argentina. Animal Production 45: 459464.Google Scholar
Schirar, A. and Levasseur, M. C. 1989. Resumption of ovarian activity in post-partum ewes: carry-over effect of the corpus luteum of pregnancy. Animal Reproduction Science 19: 9197.CrossRefGoogle Scholar
Schirar, A., Meusnier, C., Paly, J., Levasseur, M. C. and Martinet, J. 1989. Resumption of ovarian activity in post-partum ewes: role of the uterus. Animal Reproduction Science 19: 7989.CrossRefGoogle Scholar
Statistical Analysis Systems Institute. 1987. SASI STAT Guide for Personal Computers, Version 6. SAS, Cary, NC.Google Scholar
Wilson, R. T. 1989. Reproductive performance of African indigenous small ruminants under various management systems: a review. Animal Reproduction Science 20: 265286.CrossRefGoogle Scholar
Wright, P. J., Geytenbeek, P. E., Clarke, I. J. and Findlay, J. K. 1984. Induction of plasma LH surges and normal luteal function in acyclic post-partum ewes by the pulsatile administration of LH-RH. Journal of Reproduction and Fertility. 71: 16.CrossRefGoogle ScholarPubMed
Yenikoye, A. 1988. Seasonal variations in sexual activity and endocrine changes associated with follicular maturation and development in the Peulh ewe. Proceedings of the Research Coordination Meeting on Isotope Aided Studies on Livestock Production in Mediterranean and North African Countries, March 1987, Rabat, Morocco, pp. 173201.Google Scholar